Mysterious clouds could offer new clues on dark matter

Dr Lilli Sun is on the hunt for boson clouds - a key contender for dark matter. Photo: Tracey Nearmy/ANU - The hunt for gravitational waves, ripples in space and time caused by major cosmic cataclysms, could help solve one of the Universe's other burning mysteries - boson clouds and whether they are a leading contender for dark matter. Researchers are using powerful instruments, like the advanced Laser Interferometer Gravitational-Wave Observatory (LIGO), advanced Virgo, and KAGRA, that detect gravitational waves up to billions of light years away to locate potential boson clouds. Boson clouds, made up of ultralight subatomic particles that are almost impossible to detect, have been suggested as a possible source of dark matter - which accounts for about 85 per cent of all matter in the Universe. Now a major new international study carried out in the LIGO-Virgo-KAGRA collaboration and co-led by researchers from The Australian National University (ANU), offers one of the best leads yet to hunt down these subatomic particles by searching for gravitational waves caused by boson clouds circling black holes. Dr Lilli Sun, from the ANU Centre for Gravitational Astrophysics, said the study was the first all-sky survey in the world tailored to look for predicted gravitational waves coming from possible boson clouds near rapidly spinning black holes. "It is almost impossible to detect these ultralight boson particles on Earth," Dr Sun said.